Ed Miliband said Cameron had effectively been called a loser this week by Nick Boles, a Tory planning minister, who said many people do not trust the Conservatives enough to vote for them.
Photograph: PA

A former Labour minister sparked a series of vicious insults during prime minister's questions after David Cameron read out one of his tweets suggesting Ed Miliband did not look like a future leader in waiting.

Tony McNulty, a former MP and minister, tweeted that Miliband appeared to be indulging in "partisan Westminster Village knockabout" and claimed the public were "desperate for a PM in waiting who speaks for them".

This was seized on by aides to Cameron who passed him a note while he was at the despatch box, allowing him to taunt Miliband with the criticism within minutes of it being posted.

As the leaders continued to exchange verbal blows, McNulty hit back online, claiming it was weak and vacuous of Cameron to read out his tweets in the chamber when he was meant be engaged in serious debate.

Miliband had a raft of insults of his own, as he said Cameron had effectively been called a loser this week by Nick Boles, a Tory planning minister, who claimed many people did not trust the Conservatives enough to vote for them.

"What you have shown comprehensively today is you have no answers on the cost of living crisis facing families up and down the country," the Labour leader said. "That is the truth and your close friend [Boles] is right. He says this: 'There are many people who do not like the Tory party and don't trust their motives.'

"And he says the prime minister is not the man to reach them. What he is really saying is this prime minister is a loser."

Cameron responded with an attack about Paul Flowers, the former Co-op Bank chairman accused of buying drugs and financial incompetence, who helped approved loans to Labour, and a message sent by one of Miliband's economic advisers suggesting Ed Balls was a "nightmare".

"You can't even ask about banking because you're mired in your own banking scandal," he said. "What we've learned in the last fortnight is you are too weak to stand up to your paymasters in the trade unions, too weak to stand up to your bankers and too weak to stand up to shadow chancellor Ed Balls.

"We all know it would be a nightmare and that's why we are dedicated to making sure the British people don't have to live through it."

The tit-for-tat continued as Miliband accused the Conservatives of double standards over political donations. "Let's talk about the people you associate with," he said. "You've taken nearly £5m from Michael Spencer, whose company was found to be rigging Libor rates. You've got a party chairman who operated a company under a false name and was investigated for fraud.

"You've taken millions from tax exiles and tax avoiders, your party has never paid back the money from Asil Nadir and they're just the people I can talk about in this House. Now, didn't [Boles] have it right yesterday when he said this: 'The single biggest problem facing the Conservative Party is being seen as the party of the rich'?"

"They are going round saying children's centres are safe and there is no threat to them," Miliband said. "But things are so bad you have even signed a petition in your own area to save your local children's centre. Now can you clarify is the petition addressed to your local Tory council or are you taking it right to the top?"

Cameron claimed only 1% of Sure Start children's centres had closed, and said more people were using them than ever. "The figures are, because you don't want to give the figures, there are 3,000 children's centres," he said. "And the point I will make is this: this government could hold its head up high because we're actually increasing the money that is going to local councils for children's centres. That is what is happening under this government."